Colorado produced nearly 48 million barrels of oil in 2012, which ranked as the state’s second-highest level of oil production on record, according to a Denver Business Journal review of records from the Colorado Oil & Gas Conservation Commission (COGCC).

As of Monday morning, preliminary tallies of Colorado’s 2012 production stood at 47,911,393 barrels of oil — 22 percent above the 39,124,879 barrels produced in 2011, according to the COGCC.

The state’s record year was 1956, when Colorado produced 58,564,000 barrels of oil, according to the Rocky Mountain Association of Geologists.

Oil and gas companies have 45 days after the end of a month to report production and sales information for the month. The COGCC’s staff is now working to finalize 2012 production figures.

Colorado’s oil production has grown rapidly in the last few years as energy companies have explored for, and found, oil in the state’s Niobrara formation north of Denver.

And based on current trends, Colorado oil production could grow even more in years to come.

Energy companies have said they plan to spend billions in the next few years developing the Niobrara play.

But concerns have risen about drilling rigs creeping closer to suburban communities, leading to clashes between state and local officials about which jurisdiction is better suited to oversee the industry.

In November, voters in Longmont approved a ban on hydraulic fracturing (fracking) operations within the town limits. The practice, which uses water, sand and trace amounts of chemicals to crack underground rock formations to allow oil and gas to flow into the well, is key to accessing the resources. The vote has drawn a lawsuit by the Colorado Oil & Gas Association.

The state also is suing Longmont over the city council’s decision last summer to enact new regulations that include a prohibition on drilling within the city’s residential areas.

And on March 5, Fort Collins’ city council voted to ban fracking within that city’s boundaries, a move state officials have said they consider illegal.